Don't miss our weekly PhD newsletter | Sign up now Don't miss our weekly PhD newsletter | Sign up now

  Race structure and pathogenicity mechanisms in Pseudomonas syringae pv. syringae, the causal agent of brown spot of Phaseolus vulgaris (common bean)


   Department of Plant Sciences

This project is no longer listed on FindAPhD.com and may not be available.

Click here to search FindAPhD.com for PhD studentship opportunities
  Prof G Preston  Applications accepted all year round

About the Project

BACKGROUND

Beans provide one of the most important staple sources of dietary protein in many parts of Africa and worldwide, and are an important part of the horticultural export market. However, diseases of beans caused by bacterial pathogens can results in a significant loss of yield and quality. Bacterial diseases are primarily managed through the use of resistant plant varieties, in conjunction with seed certification and crop management practices. However, for some diseases, such as the brown spot pathogen, Pseudomonas syringae pv. syringae (Pss), a disease of emerging importance on bean in South Africa, there is limited information available on potential sources and mechanisms of resistance.
Pss causes a disease of bean known as brown spot, which is associated with the development of brown, necrotic lesions on leaves and pods. On leaves, old lesion centres may fall out, leading to “shot holes” or a tattered appearance of affected leaves. When young pods are infected they may become bent and twisted. Unlike many diseases caused by pathovars of P. syringae, the host range of Pss is very large, ranging from Phaseolus vulgaris (common bean), through to Glycine max (soybean), Pisum sativum (pea) and Vigna unguiculata (cowpea). Brown spot is generally regarded as a warm weather disease, causing the most damage when temperatures range from 27°C to 30°C. Brown spot-tolerant bean cultivars have been reported, but there is little resistance available in commercial cultivars.

PROJECT AIM

The aim of this project is to investigate the potential for breeding for resistance to Pss in common bean. The initial objective of the project will be to characterise a set of isolates of Pss that have been recently isolated in South Africa at a genomic, phylogenetic and phenotypic level. A subset of these isolates will then be used to investigate the molecular mechanisms involved in pathogenesis by Pss, to determine whether there is evidence of non-specific or race-specific resistance to Pss in bean accessions, and to investigate the basis of this resistance. The project will be undertaken in collaboration with Dr. Deidre Fourie (ARS, South Africa).

STUDENT PROFILE

The student appointed to this project will gain experience in microbiology, bioinformatics, plant science, molecular genetics, bioimaging and biochemistry. Students should also be able to demonstrate strong mathematical or statistical skills. It would suit a student with a relevant academic background and proven research experience in a relevant discipline.

APPLICATION DEADLINES

There are three application deadlines, but you are strongly encouraged to apply in November or January.

- Friday 16 November 2018
- Friday 25 January 2019
- Friday 1 March 2019

* Note: Applications must be submitted by 12 noon (midday) on these days.

Please ensure that you contact potential supervisors well in advance of these deadlines. Later applications may be considered if places are available.

Funding Notes

Prospective students are encouraged to apply to the Oxford Interdisciplinary Bioscience DTP. International applicants are encouraged to explore scholarship options that are available to them through the University of Oxford, their home countries or organisations such as the Commonwealth Scholarship Commission.

References

Preston G.M. (2017). Profiling the extended phenotype of plant pathogens. Molecular Plant Pathology 18, 443-456
Neale H.C., Laister R., Payne J., Preston G., Jackson R.W., Arnold D.L. (2016). A low frequency persistent reservoir of a genomic island in a pathogen population ensures island survival and improves pathogen fitness in a susceptible host. Environmental Microbiology. 18, 4144-4152.
O'Leary, B. M., Neale, H. C., Geilfus, C. -M., Jackson, R. W., Arnold, D. L., and Preston, G. M. (2016) Early changes in apoplast composition associated with defence and disease in interactions between Phaseolus vulgaris and the halo blight pathogen Pseudomonas syringae pv. phaseolicola. Plant, Cell and Environment. 39, 2172-84.
Arnold D.L., Lovell H.C., Jackson R.W., Mansfield J.W. 2011. Pseudomonas syringae pv. phaseolicola: from ‘has bean’ to supermodel. Molecular Plant Pathology 12: 617-27
Tock A.J., Fourie D., Walley P.G., et al. (2017) Genome-wide linkage and association mapping of halo blight resistance in common bean to race 6 of the globally important bacterial pathogen. Frontiers in Plant Science. 8:1170.

How good is research at University of Oxford in Biological Sciences?


Research output data provided by the Research Excellence Framework (REF)

Click here to see the results for all UK universities